EFT or eft may refer to:

• Eft, the terrestrial juvenile phase of a newt
• Effective field theory, an approximate theory to describe physical phenomena
• Ewing family of tumors, a group of cancers

A newt is a semiaquatic amphibian of the family Salamandridae, although not all aquatic salamanders are considered newts. Newts are classified as a part of the salamandrid subfamily Pleurodelinae, and can be found in North America, Europe and Asia.